Tuesday, January 5, 2010

A Blast from the LSAT Past

I may be in the minority, but my favorite part of the LSAT was the logic games section. Someone recently asked me what kind of questions appear on the test, and it inspired me to share a game with our readers. See if you can figure it out!

Hans is considering purchasing each of six items arranged from left to right on a shelf at the travelers' warehouse—a razor, a stereo, a television, a UV lamp, a video camera, and a watch. Each of these items is powered either by batteries or by an adapter, but not by both. The following conditions apply:

  1. The UV lamp is either the leftmost or the rightmost item on the shelf.
  2. No item powered by batteries is adjacent to any other item powered by batteries.
  3. The watch is powered by batteries.
  4. The fourth item on the shelf is not powered by an adapter.
  5. The razor, which is powered by batteries, is to the left of the watch, and to the right of the video camera and the stereo.

Which of the following could be true?

(A) The UV lamp is the sixth item on the shelf.

(B) The razor is the third item on the shelf.

(C) The fifth item on the shelf is powered by batteries.

(D) The stereo is powered by batteries.

(E) Both the UV lamp and the video camera are powered by batteries.

8 comments:

  1. No, I think it's C

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  2. No, I believe it is D.

    1) Lamp
    2) Stereo
    3) Camera
    4) Razor (batteries)
    5) TV
    6) Watch (batteries)

    ReplyDelete
  3. Ha. I found my Logic Games Bible when I was moving. It brought back fond memories. Definitely enjoyed the logic games more than the reading comp section, with its passages on exciting stuff like mollusks and aboriginal pygmy wind instruments. If only I could remember the Bible's tricks, maybe I'd be able to answer the question...

    ReplyDelete
  4. ANSWER: D

    Choices A, B, and C directly violate our sketch, which tells us that U is first, R is fourth, and the fifth item is powered by an adapter.

    If, as in choice D, S is powered by batteries, it must be in slot 2, since the item in slot 3 is powered by an adapter. This, means V must be in slot 3, and U must be powered by an adapter, since two consecutive items cannot be powered by batteries.

    Sketch:
    1 2 3 4 5 6
    Item U S V R T W
    Power a b a b a b


    This is an acceptable sketch, so choice D is correct.

    As for choice E, if both U and V are powered by batteries, V must be in slot 2, since the item in slot 3 is powered by an adapter. Since we cannot have items in consecutive slots powered by batteries, choice E can also be eliminated.

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  5. For those who need additional practice, we offer immediate print access to all available logic games.

    ReplyDelete
  6. I love these...

    :-)

    ReplyDelete
  7. Here is what I have: took a few minutes to diagram and only seconds to answer the questions- it's all about the diagrams!!!

    L _ _ _ _ _ or _ _ _ _ _ L

    NOT BB (not two Batteries together), so, ABA (Adapter, Batteries, Adapter)

    W/B (Watch = Batteries)

    4th item = B, so, 3rd and 5th are adapters, ABA

    Camera/Stereo < Razor < Watch


    This gives us an initial sketch of the following two options:

    L _ _ _ _ _ or _ _ _ _ _ L
    A/B A/B A B A B

    We know the watch and razor are both powered by batteries. It must go C/S < R < W Therefore: we know that slots 4 and 6 are R and W respectively leading us to:

    L C/S C/S R T W
    Since L must be 1st or last, and W can only go last, L must be first.
    (5th spot only option left for T)

    Now we can answer the questions posed.

    Anywhere there is a letter is a MUST or CANNOT BE. Anywhere there is a choice is a POSSIBLE or COULD BE TRUE/COULD BE FALSE

    Hope that helps everyone!!!

    ReplyDelete

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